What is the easiest/best way to distinguish between the 2 species by just looking? There is a pet shop close by that has captive bred seahorses (supposedly), but the employee that purchased them quit and left. I'm pretty sure they are erectus or reidi (the tag says "Hippocampus ssp"). Are there any particular features I can look for to determine the species? Thanks. I'm asking because my students raised erectus a couple of years ago, and the 2 remaining girls need boyfriends and I guess I'm going to break down and spend my own money on some horses for my students.